The temperature in Mitribah, Kuwait, surged on Friday to a blistering 54 degrees Celcius (129.2 F). And on Saturday in Basra, Iraq, the mercury soared to 53.9 C (129.0 F).

If confirmed, these incredible measurements would represent the two hottest temperatures ever recorded in the Eastern Hemisphere, according to Weather Underground meteorologist Jeff Masters and weather historian Christopher Burt.

It's also possible that Mitribah's 129.2-degree reading matches the hottest ever reliably measured anywhere in the world. Both Mitribah and Basra's readings are likely the highest ever recorded outside of Death Valley, California.

Death Valley currently holds the record for the world's hottest temperature of 56.7 C (134.1 F), set July 10, 1913. But Weather Underground's Burt does not believe it is a credible measurement.


"[T]he record has been scrutinised perhaps more than any other in the United States," Burt wrote. "I don't have much more to add to the debate aside from my belief it is most likely not a valid reading when one looks at all the evidence."

If you discard the Death Valley record from 1913, the reading from Mitribah would tie the world's highest known temperature, also observed in Death Valley on June 30, 2013, and in Tirat Tsvi, Israel, on June 22, 1942. But Masters says the Israeli measurement is controversial.

Basra, the city of 1.5 million about 120km northwest of the Gulf, has registered historic heat on two straight days. On Friday, it hit 53.6 C, the highest temperature ever recorded in Iraq, which it then surpassed on Saturday, rising to 53.9 C.

While the Middle East's highest temperatures have occurred in arid, land-locked locations, locations along the much more sultry Gulf and Gulf of Oman have faced the most oppressive combination of heat and humidity. Air temperatures of about 38 C combined with astronomical humidity levels have pushed heat index values, which reflect how hot the air feels, literally off the charts.

In Fujairah, on the east coast of the United Arab Emirates, the dew point - a measure of humidity - reached 32 C on Friday. The dew point, combined with the air temperature of 36 C, computes to a heat index of over 60 C.

But this combination of temperature and humidity is so extreme that it's beyond levels the heat index is designed to measure. The index, developed by R.G. Steadman in 1979, is intended to compute values up to only about 57.7 C.

In Bandar Mahshahr, Iran, on Friday, the air temperature soared to 41 C, which, combined with a dew point of 30 C, would produce a heat index over 60 C, also over the limit. These conditions were only slightly less extreme than on July 31 last year, when Bandar Mahshahr posted an air temperature of 46 C and dew point of 32 C, which resulted in an over-the-limit heat index of 74 C. Bandar Mahshahr sits adjacent to the Gulf in southwest Iran.

In the much more arid Basra, the dew point was only in the 30s while the relative humidity was a bone-dry 4 per cent. These conditions produce a heat index lower than the actual air temperature, about 46 C. That is, the ultra-dry air made it feel not as hot.

The torrid conditions observed in the Middle East over the last two northern summers may be a harbinger of even more extreme heat in the future. A study published in the journal Nature Climate Change in October cautioned that by the end of the century, due to climate change, temperatures may become too hot for human survival.

In March, the National Academy of Sciences published a report that stated worsening heat waves are among the weather events that can be most easily connected to human-caused climate change.

All record temperatures noted are preliminary and await validation from the World Meteorological Organisation.